Week 4

Question 1

Which of the following is NOT needed to perform an analysis using 3D motion capture

Answer 1

Force Plate

Question 2

How many cameras (minimum) are needed for 3D motion capture

Answer 2

2

Question 3

The entire biomechanics lab from wall to wall is part of the capture volume

Answer 3

False

Question 4

In order for the cameras to all “talk” to each other, what step must be taken during calibration

Answer 4

A wand is waved for a period of time in the capture volume

Question 5

Any place within the capture volume could be defined as the origin of the xyz coordinate system

Answer 5

True

Question 6

How many markers (minimum) are necessary for each body segment

Answer 6

3

Question 7

Using 3D motion capture, the pelvis angle would be measured as the angle between the trunk and the thigh segments

Answer 7

False

Question 8

In 3D motion capture, joint angles can be calculated similar to 2D motion capture using the x-y coordinates of as few as 3 reflective markers

Answer 8

False

Question 9

Plug-in Gait uses standardized marker placements that the 3D motion capture software can recognize and then quickly compute joint angles during walking gait

Answer 9

True

Question 10

Which of the following has been demonstrated as a symptom of concussion using 3D motion capture

Answer 10

Increased medial lateral sway during walking

Question 11

How many cameras minimum are needed for 3D motion capture

Answer 11

2

Question 12

How many frames do you need to calibrate using the calibration wand

Answer 12

1000 frames

Question 13

The calibration wand is set up at

Answer 13

xyz 0,0,0

Question 14

What body segments define the ankle

Answer 14

Foot and shank

Question 15

What body segments define the knee

Answer 15

Shank and thigh

Question 16

What body segments define the hip

Answer 16

Pelvis and thigh

Question 17

What body segments define the pelvis

Answer 17

Pelvis is a segment angle

Question 18

What body segments define the trunk

Answer 18

Trunk is a segment angle

Question 19

What body segments define the shoulder

Answer 19

Arm and scapula

Question 20

What is a capture volume

Answer 20

The volume of space representing the coverage area of the 3D motion capture cameras within a biomechanics lab

Question 21

The wand has two functions

Answer 21

Calibrates cameras

Defines xyz origin

Question 22

3D motion capture vs 2D motion capture characteristics

Answer 22

3D:
Accurate
Repeatable
3 Planes of motion
Automatic processing

2D:
Money - cheap
Time
Accessibility

Question 23

How many markers in total in plug in gait method

Answer 23

16 markers

Question 24

Which side of the body has slightly higher marker placement and what body parts are they

Answer 24

Right thigh

Right Tibia

Question 25

Plug in gait is…

However is…

Requires…

Answer 25

Commonly used

Limited

1 extra step - anthropometric data

Question 26

What anthropometric data does plug in gait require

Answer 26

Height

Weight

Leg length

Knee width

Ankle width

Question 27

What can 3D motion capture be used for in real life

Answer 27

Animated video games

Movie characters

3D joint angles during movement